[PATCH] drm/bridge/synopsys: dsi: allow sending longer LP commands

From: Yannick Fertre
Date: Wed Jul 01 2020 - 10:31:46 EST


From: Antonio Borneo <antonio.borneo@xxxxxx>

Current code does not properly computes the max length of LP
commands that can be send during H or V sync, and rely on static
values.
Limiting the max LP length to 4 byte during the V-sync is overly
conservative.

Relax the limit and allows longer LP commands (16 bytes) to be
sent during V-sync.

Signed-off-by: Antonio Borneo <antonio.borneo@xxxxxx>
---
drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index d580b2aa4ce9..1a24ea648ef8 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -360,6 +360,15 @@ static void dw_mipi_message_config(struct dw_mipi_dsi *dsi,
bool lpm = msg->flags & MIPI_DSI_MSG_USE_LPM;
u32 val = 0;

+ /*
+ * TODO dw drv improvements
+ * largest packet sizes during hfp or during vsa/vpb/vfp
+ * should be computed according to byte lane, lane number and only
+ * if sending lp cmds in high speed is enable (PHY_TXREQUESTCLKHS)
+ */
+ dsi_write(dsi, DSI_DPI_LP_CMD_TIM, OUTVACT_LPCMD_TIME(16)
+ | INVACT_LPCMD_TIME(4));
+
if (msg->flags & MIPI_DSI_MSG_REQ_ACK)
val |= ACK_RQST_EN;
if (lpm)
@@ -611,14 +620,6 @@ static void dw_mipi_dsi_dpi_config(struct dw_mipi_dsi *dsi,
dsi_write(dsi, DSI_DPI_VCID, DPI_VCID(dsi->channel));
dsi_write(dsi, DSI_DPI_COLOR_CODING, color);
dsi_write(dsi, DSI_DPI_CFG_POL, val);
- /*
- * TODO dw drv improvements
- * largest packet sizes during hfp or during vsa/vpb/vfp
- * should be computed according to byte lane, lane number and only
- * if sending lp cmds in high speed is enable (PHY_TXREQUESTCLKHS)
- */
- dsi_write(dsi, DSI_DPI_LP_CMD_TIM, OUTVACT_LPCMD_TIME(4)
- | INVACT_LPCMD_TIME(4));
}

static void dw_mipi_dsi_packet_handler_config(struct dw_mipi_dsi *dsi)
--
2.17.1